Brown owl
The Tawny owl (Strix aluco) is commonly found in woodlands across much of Eurasia and North Africa, and has 11 recognized subspecies. The Tawny owl is non-migratory and highly territorial: as a result, when young birds grow up and leave the parental nest, if they cannot find a vacant territory to claim as their own, they will often starve. This nocturnal bird of prey is able to hunt successfully at night because of its vision and hearing adaptations and its ability to fly silently.
The Tawny owl is quite distinct in its large, rounded head. The Tawny owl has no ear tufts but does possess a prominent facial disc rimmed in slightly dusky feathers. Its underparts are pale with dark streaks, and the upper parts are either rufous, brown, or grey. The typical rich brownish color often camouflages it well against a variety of woodland types. The Tawny owl has relatively thick and heavy legs and feet and its talons are rather powerful and quite decurved. In flight this bird can appear fairly big and broad, large-headed, and rounded on the wings.
Tawny owls are found throughout Europe, Western and Central Asia, and North Africa. The preferred habitat of these birds is temperate deciduous forest and mixed forest with some access to clearings. They may also be found in coniferous forests, taiga, riverine forests, parks, large gardens with old trees, open landscapes with wooded patches, and avenues of trees in open agriculture.
Tawny owls are non-migratory and generally solitary birds. They are usually quite nocturnal but are sometimes briefly active during daylight. During the day, Tawny owls may roost amongst dense foliage, quite often on a branch close to the trunk, or in a natural hole in a tree or rock formation, in a hole or crevice of a wall. These are highly territorial owls that seldom leave their home range and defend their territory at any time of the year. Both males and females maintain territories through hooting songs. Tawny owls are opportunistic and generalized predators. They prefer to hunt between dusk to midnight and often follow an erratic hunting pattern, perhaps to sites where previous hunts were successful. Normally these owls hunt from a perch but may also hunt from the flight. This occurs from 2 to 3 m (6.6 to 9.8 ft) over the ground, often over open habitats such as bushes, marsh, or grassland, forming a quartering or zigzag pattern over the opening. During these flights, they cover about 30 to 50 m (98 to 164 ft) before changing direction. Tawny owls may use another hunting technique - hunting from the ground where they often take beetles or other insects; they may also “leap” upon from a ground vantage point in order to capture a vole, quite like foxes often do. Tawny owls communicate with the help of various calls. Males' territorial call is a quavering song 'hoo...ho, ho, hoo-hoo-hoo-hoo' or 'whooooh uk whooooook'. Females' territorial call is somewhat like the males' but is hoarser, less clear, and somewhat higher in pitch, transcribed as 'cher oooOOooo' followed by 'chro cher-oooOOooo cooEEooooo'. Apart from territorial calls, other vocalizations of Tawny owls include piercing 'coo-wik' or 'cu-weeehl cries', apparently expressing aggression. When disturbed at the nest, these owls may utter a series of yelping 'uett-uett-uett..' notes. Males sometimes emit a pig-like grunting during courtship displays. Some mysterious calls recorded for Tawny owls have included tooting, chittering, crowing, screeching, or mewing, as well as soft, plaintive squeaks by females.
Tawny owls are carnivores and take an extremely wide range of prey species. They generally prefer small mammals in their diet, especially various species of rodents but will also eat birds, amphibians, and insects as well as sometimes reptiles and fish.
Tawny owls are monogamous and mate for life. Young birds select territories and look for mates in autumn and tend to be very vocal, especially males. Due to their highly territorial behavior, young birds frequently struggle to establish a territory unless a nearby adult dies. When the pair is formed, the male advertises several potential nest sites to his mate by singing at the entrance, slipping inside, and so on until the female finally selects one. The typical nest site is a tree hollow, wherein the owls will nest directly on the interior hole's surface. Laying usually begins in March-early April, sometimes as early as February. The female typically lays a relatively small clutch of 3-5 eggs which are pure white, smooth, or slightly glossy in texture, and vary little in size. The female incubates alone, starting with the first egg for 28-29 days, and is fed by the male. Young begin to call in about 24 hours before they hatch. The female broods the owlets closely until 10-15 days. They are fed small bits of meat for about 12 days, at which point the owlets open their eyes and begin to more actively beg. When they are 21-25 days old, the young are stronger on their legs and feet and begin to spend much time around the entrance of the nest hole. They begin to emerge fully about 3-5 days later. Finally, at 29-37 days, the owlets fledge but take about another 2 weeks before they can fly strongly. They become independent at 3 months of age and start breeding at one year but more commonly when they are 2-3 years old.
Tawny owls are not considered endangered or globally threatened. However, they may suffer from several factors. Besides natural causes such as predation and starvation, collision with vehicles, power lines, any other kind of wire collision and other manmade objects is a regular cause of Tawny owl mortality. Occasionally, these birds also suffer from human persecution including egg-collecting, shootings, and poisonings.
According to the IUCN Red List, the total Tawny owl population size is around 1,000,000-2,999,999 mature individuals. In Europe, the breeding population consists of 535,000-939,000 pairs, which equates to 1,070,000-1,880,000 mature individuals. Overall, currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Tawny owls play an important role in their ecosystem. They control populations of various mammals and particularly rodents that make up a big part of their diet.
